Micrometer



Dec. 27, 1927. I 1,653,854

J. A. HUGE MICROMETER Filed Sept. 22. 1926 Inventor fit) Patented Dec.27, 1927.

UNITED; STATES PAT MICROMETER.

Application filcdfieptember 22, 1926. Serial ififo 136.937

This invention relates to an improved micrometer and has more particularreference to an inside micron'ieter head. i

lh'iefiy, the improved instrument COUL- prises a"cylindrical shellhaving means at one end to acconni'iodate a manually adjustablemicrometer and having means at its opposite end accommodating anautomatically adjustable means for cooperationwith the manually adjustedmeans, to permit more accurate nieasurenient to be obtained.

lilore specifically, the invention relates to a cylindrical shell havingan internallyscrew threaded cylinder at one end to 30001111110 date themanually adjustable micrometer, the shell being constructed at itsopposite end to accommodate. a spring pressed plunger and measuringelement which actuates an indicator such as may he more readilyvisualized under conditions such as make the reading of the ordinarymicrometer di'll'icult and i111 certain. l

Other features and ad *antages will becoi ne apparent during (the courseof the fol lowin; description.

In the accompanying drawings, where n like reference characters areen'iployed to ('lesignate like parts throughout the same:

Figure 1 is atop plan view of a measuring instrument constructed inaccordancewith the invention,

Fig. 2 is a central longitudinal view throughthe same, showing parts inelevation,

Fig. 3 is a transverse section taken ap proximately upon the plane ofthe line 33 of Fig. 1 looking in the direction of the arrow.

Referring to the drawings in detail, it will be seen that thereferencecharacter 1 designates the cylindrical shell which is open atits opposite ends and provided at its center with a partition 2.Extending from one side of the partition is a cylinder 3 located withinthe shelland terminating in spaced relation from the left-hand end. Inthis connection it will be noted thatthe left-hand end is provided witha bevel equipped with customary graduations &. Moreover, it will lienoted that the cylinder 3 is internally screw-threaded and is spacedfrom the surrounding wall of the shell. This a rangement serves toaccommodate a somewhat conventional form of manually adjustable insidemicrometer. The part of the micrometer fitting into the screw threadedcylinder 3 cooperates with the aforesaid graduations el in an obviousmanner. Extending from the oppositeside ot the partition is .arelatively short cylindrical guide 5 inwhi ch the nner end portion ottheplunger and the measuring stem 6 are slidably mounted. In thisconnection it will be noted that the partition 2 is provided with ablepassage of the. inner :lrce end portion of the stun. ilioreover, thestem is pro vided with a circular shoulder 6 slidaible in the guide anda coiled springv 7 surrounds the stern between the shoulder tion. and isconfined in said guide. The spring is enceptirma-lly sensitive and willpermit sliding movement of the stem assoon as a very slight pressure;isbrought to bear upon the same. The intermediate portion of the stemprovidedwith a gear 8 which co-. operateswith centrally disposed teeth 9on a rotatably mounted shait 10. The teeth are (harmed y by. providingcircumfereiitially spaced grooves inthe shaft. Moreover, the shaft ispointed at one end, as at 10 and journaled in the shell and its oppositeendis rotatably mounted in a part of theeigt ernal gauge 11. Inconnection with the gauge it is to he statedthat thisincludes-a suitabledialand a transparent glass 12; In addition there is a pointer 13 outheend of the shaft which cooperates with the dial which is preferablygraduated in thousandths of an inch.

Movement of the stem in one direction is limited by the stop 1% and inthe opposite direction it is limited by a similar stop 15. The endportion 16 extends through a closing head 17; This head is removahlyfitted into the adjacent end of the aforesaid cylindrical shell and themeasuring stem normally projects a predetermined distance beyond thebase of the head as shown. The head is provided on one side with asocket and located in this socket is a plate 18, a coil spring 19, andan operating member 20. This member bears against the spring and ispreferably provided on its outer end with a finger piece 21. Theadvantage of this construction is that in case the gauge cannot be readconveniently, the member 20 can be tightened to hold the stem 6 in theposition to which it has been moved. In turn, the indicating finger 13will be held. Inthis way the instrument can be removed from the work andthe gauge easily read, at

which the stem can be released to resume its normal position under theaction of the cur rQEFtCtZ.

an opening; tin. slid and the parti-j sprin The micrometer is of courseused as any other inside micrometer but the par ticular constructionshown will save much time and will insure accuracy in measurement.Instead of having to adjust by touch, as is now customary toone-thousandth of an inch, the stem can be adjusted within onehundred-thousandthof an inch while and in such position the dial can beconveniently read. The supplemental plunger and indicating meansfmaybeoperated eiiiciently in'conjunction with the manuallyadjustablemicrometer (not shown) on the opposite end to insure an accurate andtrue measurement.

The advantages andconstruction w ll become apparent from the foregoingdescription and drawin Therefore, a more lengthy description is thoughtunnecessary.

I claim;

1. In a measuring instrument,a shell provided with an internallyscrew-threaded cylinder atone end to accommodate a manually adjustableinsidemicrometer, a head at the opposite open end of said shell, saidhead being provided with aguide opening, astem mounted for slidingmovement in saidshell, and having one of its ends projectable throughand beyond said guideopening and its other end terminating in said shellspring means connected with the last named end ofthe stem for normallypushing the opposite end of the same through'said guide opening, a gearcarriedby the intermediate portionlof the stem, a shaft located in andextending acrosssaidcylinder at right anglesito said stem and providedwith teeth cooperable with said gear, a pointer carried by one "end ofsaid shaft, and a gauge mounted on said'body and includlng a dial wlthwhich and polnter 1s cooperable.

2. In a measuring instrument, an open ended cylindrical shell providedwith a central apertured partition, a cylinder located within one endportion otthe shell and connected with said partition, said cylinderbeing provided with screw threads and being adapted to operate asnecting means for a manually adjustable inside niicroineter, acylindrical guide carried by the opposite side of said partition, aheadcarried by one end of the shell andprovided with a central guide openingin alinen'ient with said cylindrical guide, a stemslidablc through theopening insaid partition at one end and through the opening in said headat: its other end, said stem being provided with an intermediate gear, ashaft mounted for rotation in saidshell and extending across said stemat right angles to the latter and provided with teeth coopera mountingand coniii able with the teeth of said gear, spring meansassociated withthelastnamed end of said stem and located in said cylindrical guide forpushing said stein outwardly through and beyond the guide opening insaid head, a pointer carried by said shaft, a gauge mounted on the bodyend including a dial with which said pointer is cooperable, and amanually adjusted retaining device carried by said head and cooperablewith said stem for holding the latter in a set position. v

In testimony whereof I affix my signature;

JOHN aneusrus noon.

